1 files changed, 12 insertions, 20 deletions

diff --git a/drivers/mtd/nand/atmel_nand.c b/drivers/mtd/nand/atmel_nand.c
index 6fae04b3fc6..950646aa4c4 100644
--- a/drivers/mtd/nand/atmel_nand.c
+++ b/drivers/mtd/nand/atmel_nand.c
@@ -209,22 +209,8 @@ static int atmel_nand_dma_op(struct mtd_info *mtd, void *buf, int len,
 	int err = -EIO;
 	enum dma_data_direction dir = is_read ? DMA_FROM_DEVICE : DMA_TO_DEVICE;
 
-	if (buf >= high_memory) {
-		struct page *pg;
-
-		if (((size_t)buf & PAGE_MASK) !=
-		    ((size_t)(buf + len - 1) & PAGE_MASK)) {
-			dev_warn(host->dev, "Buffer not fit in one page\n");
-			goto err_buf;
-		}
-
-		pg = vmalloc_to_page(buf);
-		if (pg == 0) {
-			dev_err(host->dev, "Failed to vmalloc_to_page\n");
-			goto err_buf;
-		}
-		p = page_address(pg) + ((size_t)buf & ~PAGE_MASK);
-	}
+	if (buf >= high_memory)
+		goto err_buf;
 
 	dma_dev = host->dma_chan->device;
 
@@ -280,7 +266,8 @@ static void atmel_read_buf(struct mtd_info *mtd, u8 *buf, int len)
 	struct nand_chip *chip = mtd->priv;
 	struct atmel_nand_host *host = chip->priv;
 
-	if (use_dma && len >= mtd->oobsize)
+	if (use_dma && len > mtd->oobsize)
+		/* only use DMA for bigger than oob size: better performances */
 		if (atmel_nand_dma_op(mtd, buf, len, 1) == 0)
 			return;
 
@@ -295,7 +282,8 @@ static void atmel_write_buf(struct mtd_info *mtd, const u8 *buf, int len)
 	struct nand_chip *chip = mtd->priv;
 	struct atmel_nand_host *host = chip->priv;
 
-	if (use_dma && len >= mtd->oobsize)
+	if (use_dma && len > mtd->oobsize)
+		/* only use DMA for bigger than oob size: better performances */
 		if (atmel_nand_dma_op(mtd, (void *)buf, len, 0) == 0)
 			return;
 
@@ -599,7 +587,10 @@ static int __init atmel_nand_probe(struct platform_device *pdev)
 		nand_chip->options |= NAND_USE_FLASH_BBT;
 	}
 
-	if (cpu_has_dma() && use_dma) {
+	if (!cpu_has_dma())
+		use_dma = 0;
+
+	if (use_dma) {
 		dma_cap_mask_t mask;
 
 		dma_cap_zero(mask);
@@ -611,7 +602,8 @@ static int __init atmel_nand_probe(struct platform_device *pdev)
 		}
 	}
 	if (use_dma)
-		dev_info(host->dev, "Using DMA for NAND access.\n");
+		dev_info(host->dev, "Using %s for DMA transfers.\n",
+					dma_chan_name(host->dma_chan));
 	else
 		dev_info(host->dev, "No DMA support for NAND access.\n");